Global Positioning System (GPS) is a space-based Global Navigation Satellite System (GNSS) that computes the range from a receiver to multiple satellites. Since it was open to the civilian community, the demands for GPS have highly increased in the position-related applications such as navigation, positioning and timing. Although it has been proven to be reliable and accurate, the power of a received GPS signal is less than −120 dBm such that the GPS receiver is vulnerable to jamming or RF interference effects [1]. In order to predict the interference effect on the GPS system properly, it is important to perform a software analysis of RF interference before the hardware of the receiver system is implemented. There are numerous studies that investigated into GPS interference effects or anti-jamming methods based on the system hardware [2–3]. However, there are few studies on the software interference analysis to technically support the prediction of interference effect on the GPS receiver.